1. Field of the Invention
The invention relates to hydrodynamic torque converters and more particularly to a hydrodynamic torque converter utilizing outward pressings on the primary flange for connecting elements to the primary flange.
2. Description of the Related Art
FIG. 1, of DE 44 32 624 C1, shows a hydrodynamic torque converter with a converter housing that has, on its side facing a drive, e.g., the crank shaft of an internal combustion engine, a substantially radially-running primary flange, on which a central pin is provided for mounting in the crank shaft. Further, a housing hub is embodied on the primary flange radially outside the central pin and in a single piece with the central pin. Radially outside the housing hub there are holding means that serve, via a plate, to connect the converter housing to the drive. The connection, as shown in DE 32 22 119, is usually established via an axially elastic connecting plate, which is screwed radially inside to the crank shaft and radially outside to the holding means. This elastic connecting plate at least reduces the transmission of vibrations from the crank shaft with a component in the axial direction to the converter housing.
With respect to the torque converter described in DE 44 32 624 C1, it should be noted that the one-piece embodiment of the bearing journal and the housing hub results in a relatively complicated and massive component, which must then be attached to the relatively thinwalled primary flange by means of a welded seam. The plate with the holding means is also attached to the primary flange by welded seams. The welded seams, however, create the problem of a thermally uneven load of the primary flange, so that the danger of deformation exists. Moreover, imbalances are introduced into the converter housing, which must be eliminated by subsequent balancing measures. Overall, the embodiment of a torque converter described in the aforementioned patent document represents a relatively complicated and expensive design, in terms of production technology, and raises problems in accommodating connecting elements, such as the holding means, the housing hub or the central pin, on the primary flange of the converter housing.
The housing hub holds, via a bearing, a turbine hub of the turbine wheel. In turn, the turbine hub holds, via a tooth system, a gear input shaft in a rotation-proof fashion. The gear input shaft serves as the output of the hydrodynamic torque converter.
Utility Patent DE 87 10 517 describes and depicts a primary flange of a hydrodynamic torque converter, on which an outward pressing is created by means of material displacement starting from the side of a drive. The outward pressing penetrates an opening in an adjacent part, here, an element of a torsional vibration damper. A rear-gripping means, which grips behind the rear side of the element of the torsional vibration damper, is then created on the outward pressing by means of material compression in the opposite direction. The rear-gripping means acts as an axial securing means to axially secure the element of the torsional vibration damper relative to the primary flange. The torsional vibration damper is thus attached to the primary flange via a rivet-like connection, without suffering the disadvantages of a rivet, i.e., lack of tightness on the primary flange in the rivet extension area. However, the Utility Patent does not point to an advantageous attachment of connecting elements to the primary flange.